steering LEXUS LS600H 2017 Service Manual

3314-5. Using the driving support systems
4
Driving
LS600h/LS600hL_EE(OM50G20E)
●When driving on a road surface that is wet due to rain, previous rainfall, standing
water, etc.
●When the vehicle experiences strong up-and-down motion such as when driving
on an extremely rough road or on a seam in the pavement
●When headlight brightness at nighttime is reduced due to dirt on the lenses, or
when the headlights are misaligned
●When driving with a strong crosswind
●When driving on winding roads or roads that are uneven
●When driving on rough or unpaved roads
■When changing the tires
Depending on the tires used, such as snow tires, etc., sufficient performance may not
be maintainable.
■Warning messages for LKA
Warning messages are used to indicate a system malfunction or to inform the driver
of the need for caution while driving. ( P. 563)
CAUTION
■Before using the LKA system
Do not rely solely on the LKA system. The LKA system does not drive the vehicle
automatically, nor does it reduce the amount of care you need to take. As such, the
driver must always assume full responsibility for understanding his/her
surroundings, for operating the steering wheel to correct the driving line, and for
driving safely.
Inappropriate or negligent driving could lead to an accident.
■To avoid operating the LKA by mistake
Switch the LKA off using the LKA switch when not in use.

3354-5. Using the driving support systems
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Driving
LS600h/LS600hL_EE(OM50G20E)
Sport mode
• SPORT S mode
Assists acceleration response by controlling the hybrid system. Suit-
able for when powerful acceleration is desirable.
When not in SPORT S mode and the driv ing mode select switch is turned to
the right, the “SPORT S” indicator comes on in the multi-information display,
and the Hybrid System Indicator changes to the tachometer. ( P. 115)
• SPORT S+ mode
Helps to ensure steering performance and driving stability by simul-
taneously controlling the steering and suspension in addition to the
hybrid system. Suitable for sporty driving.
When in SPORT S mode and the driving mo de select switch is turned to the
right, the “SPORT S+” indicator comes on in the multi-information display.
■Operation of the air conditioni ng system in Eco drive mode
Eco drive mode controls the heating/cooling operations and fan speed of the air
conditioning system to enhance fuel efficiency ( P. 399). To improve air condition-
ing performance, adjust the fan speed or turn off Eco drive mode.
■Sport mode automatic deactivation
Sport mode is automatically deactivated if the power switch is turned off after driving
in sport mode.
■Driving mode pop-up display
When the driving mode is changed, the selected driving mode will be temporarily
displayed on the side display. ( P. 396)
4

3364-5. Using the driving support systems
LS600h/LS600hL_EE(OM50G20E)
The vehicle height is maintained at the selected level regardless of the
number of occupants and luggage weight.
Turns high mode on/off.
When on, the “HEIGHT HIGH” indi-
cator will come on.
■Operating sound of the air suspension compressor
When the vehicle height is lowered, such as when entering or loading the vehicle, or
high mode is selected, the compressor may operate and a whirring sound may be
heard. This does not indicate a malfunction.
Electronically modul ated air suspension
By independently controlling the damping force of the shock absorbers
for each of the 4 wheels according to the road and driving conditions
and the selected driving mode, this system achieves ride comfort with
superior steering stability, an d ensures good vehicle posture.
In addition, vehicle height can be se lected according to road and driv-
ing conditions.

3384-5. Using the driving support systems
LS600h/LS600hL_EE(OM50G20E)
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if
the brakes are applied while driv ing on a slippery road surface
◆Brake assist
Generates an increased level of braking force after the brake pedal is
depressed when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning
on slippery road surfaces
◆TRC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spin-
ning when starting the vehicle or accelerating on slippery roads
◆Hill-start assist control
Helps to prevent the vehicle from rolling backward when starting on an
incline or slippery slope
◆VGRS (Variable Gear Ratio Steering)
Adjusts the wheel turning angle in accordance with the vehicle speed
and steering wheel movement
Driving assist systems
To help enhance driving safety and performance, the following systems
operate automatically in response to various driving situations. Be
aware, however, that these system s are supplementary and should not
be relied upon too heavily when operating the vehicle.

3394-5. Using the driving support systems
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Driving
LS600h/LS600hL_EE(OM50G20E)
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to
turn the steering wheel
◆Active stabilizer suspension system (if equipped)
Reduces sway when cornering according to steering wheel movement
and the selected driving mode, in order to maintain a stable vehicle
posture
◆VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRC, VSC, hill-
start assist control, EPS and VGRS systems
Helps to maintain vehicle stability when swerving on slippery road sur-
faces by controlling the brakes, hybrid system output, steering assist,
and steering ratio
◆PCS (Pre-Crash Safety system) (if equipped)
 P. 346
◆Rear Pre-Crash Safety system (if equipped)
 P. 360
◆Emergency brake signal
When the brakes are applied suddenly, the stop lights automatically
flash to alert the vehicle behind
◆BSM (Blind Spot Monitor) (if equipped)
 P. 366

3424-5. Using the driving support systems
LS600h/LS600hL_EE(OM50G20E)
■Hill-start assist control is operational when
●The system has detected that the vehicle is moving backward.
●The shift lever is in the D or S position.
●The brake pedal is not depressed.
■VGRS is disabled when
VGRS may stop operating in the following situations.
In this event, the steering wheel may move from its straight forward position, but it
will return when the system restarts.
●When the steering wheel is operated for an extended period of time while the vehi-
cle is stopped or is moving very slowly
●When the steering wheel has been held fully to the left or right
●When the 12-volt battery is low or the voltage temporarily drops
The center position of the steering wheel may change when VGRS is disabled. How-
ever, the position will return to normal after VGRS is reactivated.
■Sounds and vibrations caused by the ABS, brake assist, TRC, VSC, hill-start assist
control and VGRS systems
●A sound may be heard from the engine compartment when the brake pedal is
depressed repeatedly, when the hybrid system is started or just after the vehicle
begins to move. This sound does not indicate that a malfunction has occurred in
any of these systems.
●Any of the following conditions may occur when the above systems are operating.
None of these indicates that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard after the vehicle comes to a stop.
●The steering wheel may be moved slightly or a sound may be heard when the
hybrid system is started or stopped. None of these indicate that a malfunction has
occurred.
■EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be heard.
This does not indicate a malfunction.
■Reactivation of the TRC/VSC systems
Even after the TRC/VSC systems have been turned off, turning the hybrid system off
and then on again will automatically reactivate the TRC/VSC systems.

3434-5. Using the driving support systems
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Driving
LS600h/LS600hL_EE(OM50G20E)
■Reactivation of the TRC system linked to vehicle speed
When only the TRC system is turned off, the TRC system will turn on when vehicle
speed increases. However, when both TRC and VSC systems are turned off, the sys-
tems will not turn on even when vehicle speed increases.
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from overheat-
ing when there is frequent steering input over an extended period of time. The steer-
ing wheel may feel heavy as a result.* Should this occur, refrain from excessive
steering input or stop the vehicle and turn the hybrid system off. The EPS system
should return to normal within 10 minutes.
*: If the LKA (Lane-Keeping Assist) system cannot operate in this case, a warning
message will be shown on the multi-information display.
■Operating conditions of emergency brake signal
When the following three conditions are met, the emergency brake signal will oper-
ate:
●The emergency flashers are off.
●Actual vehicle speed is over 55 km/h (35 mph).
●The brake pedal is depressed in a manner that cause the system to judge from the
vehicle deceleration that this is a sudden braking operation.
■Automatic system cancelation of emergency brake signal
The emergency brake signal will turn o ff in any of the following situations:
●The emergency flashers are turned on.
●The brake pedal is released.
●The system judges from the vehicle deceleration that is not a sudden braking oper-
ation.

3474-5. Using the driving support systems
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Driving
LS600h/LS600hL_EE(OM50G20E)
◆Pre-crash braking
When there is a high possibility of a frontal collision, the system warns
the driver using a warning light, warning display and buzzer. If the sys-
tem determines that a collision is unavoidable, the brakes are automati-
cally applied to help avoid a collision or to reduce the collision speed.
When the vehicle is being stopped by pre-crash braking, the brake will
be engaged for a maximum of 2 seconds and then released automati-
cally. This pre-crash braking can be canceled by depressing the accel-
erator pedal or brake pedal.
Pre-crash braking can be disabled using the pre-crash braking off switch.
◆Suspension control
When there is a high possibility of a frontal collision, the operation of
suspension control helps prevent the front of the vehicle from dropping
when the brakes are applied suddenly.
◆Steering gear control (VGRS) (vehicles with camera sensors)
When the system determines that a collision is unavoidable, the steer-
ing gear ratio is changed to help improve the response to steering
input.
◆Driver monitor system (if equipped)
When the system determines that there is a possibility of a collision, and
either the driver is not facing forward or the driver’s eyes are closed,
pre-crash warnings are given in adva nce to warn the driver. If the sys-
tem determines that the conditions to operate pre-crash alert braking
have been met even when the possibility of a collision increases further,
pre-crash alert braking will operate.
Pre-crash alert braking can be disabled using the pre-crash braking off switch.

3514-5. Using the driving support systems
4
Driving
LS600h/LS600hL_EE(OM50G20E)
●Pre-crash braking:
Vehicles without camera sensors
• The pre-crash braking off switch is not pressed.
• The VSC OFF switch is not pressed.
• Vehicle speed is greater than about 15 km/h (10 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle run-
ning ahead of you is greater than about 15 km/h (10 mph).
Vehicles with camera sensors
• The pre-crash braking off switch is not pressed.
• The VSC OFF switch is not pressed.
• Vehicle speed is greater than about 5 km/h (4 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle run-
ning ahead of you is greater than about 5 km/h (4 mph).
●Suspension control:
• Vehicle speed is greater than about 5 km/h (4 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle run-
ning ahead of you is greater than about 30 km/h (19 mph).
●Steering gear control (VGRS) (vehicles with camera sensors):
• Vehicle speed is greater than about 30 km/h (19 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle run-
ning ahead of you is greater than about 30 km/h (19 mph).
●Pre-crash alert braking (vehicles with driver monitor system):
• The pre-crash braking off switch is not pressed.
• The VSC OFF switch is not pressed.
• The system determines that the driver is not facing forward, or that the driver’s
eyes are closed.
• Vehicle speed is greater than about 40 km/h (25 mph).
• The speed at which your vehicle is approaching the vehicle running ahead of
you is greater than about 40 km/h (25 mph).
• The steering is not being turned.

3534-5. Using the driving support systems
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Driving
LS600h/LS600hL_EE(OM50G20E)
■Situations in which the pre-crash safety system does not function properly
The system may not function effectively in situations such as the following:
●On roads with sharp bends or uneven surfaces
●If a vehicle suddenly moves in front of your vehicle, such as at an intersection
●If a vehicle suddenly cuts in front of your vehicle, such as when overtaking
●In inclement weather such as heavy rain, fog, snow or sand storms
●If the vehicle is skidding when VSC is not operating
●When an extreme change in vehicle height occurs
●When only part of your vehicle’s front end collides with, or contacts, a vehicle or
object in a frontal collision
●When the radar sensor moves off position due to its surrounding area being sub-
jected to a strong impact
●If an obstacle in front of the vehicle is small
●When the system judges that the driver performed a collision avoidance operation
via the accelerator pedal, brake pedal, or steering wheel
■Automatic cancelation of the pre-crash safety system
When a malfunction occurs due to sensor contamination, etc. that results in the sen-
sors being unable to detect obstacles, the pre-crash safety system will be automati-
cally disabled. In this case, the system will not activate even if there is a collision
possibility.
■When there is a malfunction in the system
The pre-crash safety system warning light will flash and warning messages will be
displayed. ( P. 557, 563)